1. Field of the Invention
The present invention relates generally to a hinge, and more particularly to a hinge used for folding portable electronic devices. The instant invention relates to a contemporarily filed application titled “HINGE ASSEMBLY FOR FOLDABLE ELECTRONIC DEVICE” and having the same assignee with the instant application.
2. Prior Art
Hinges are almost universally used in modern portable electronic devices such as mobile phones and PDAs (Personal Digital Assistants). These portable electronic devices typically comprise two housings. Hinges are used to join the two housings together, and to enable one housing to be folded upon the other one. Normally, one of the housings is called a body and contains most of the electronic components of the portable electronic device. The other housing is called a cover and contains fewer or even no electronic components.
One kind of hinge is disclosed in U.S. Pat. No. 5,628,089 issued to Scott R. Wilcox et al (the '089 patent). In the '089 patent, as shown in FIG. 8, a hinge includes a cam follower 403, a spring 405, a cam 404, a cam follower 403 and a cap 505. The cam follower 403 is generally a hollow cylinder, being closed at one end and open at the other end. The spring 405, cam 404 and cap 505 are located in the cam follower 403 in that sequence. The cap 505 barely covers the opening of the cam follower 403. At approximately the middle of each slot 423, a hole 435 is defined. The hole 435 spans between an exterior surface 463 and an interior surface 465. The cam 404 has two rails 417 formed on an exterior surface 467 thereof. When cam follower 403 rotates, the cam 404 rotates along with it.
This kind of hinge is convenient insofar as all the components can be assembled into one part before it is used in a foldable portable electronic device. However, the cap 505 is attached to the cam follower 403 by way of barbs 411 of two arms 409 catching in the holes 435 of the cam follower 403. This linkage between the cap 505 and the cam follower 403 is not secure.
Therefore, a hinge with a relatively simple structure is desired to overcome the above-described problems.